1. Field of the Invention
This invention relates, broadly speaking, to a method of making useful materials from waste rubber and to useful articles having unusual and valuable physical, mechanical and thermal properties made therefrom.
More particularly, this invention relates to a method of making rubberized carbon black from waste rubber such as automobile tires, which waste rubber was originally compounded with carbon black, and to useful articles incorporating said rubberized carbon black.
2. Description of the Prior Art
Many processes are known for recovering the hydrocarbon content (e.g. rubber) and the carbon black content of worn automobile tires for reuse, in one form or another.
Some typical patents disclosing such processes are:
U.S. Pat. No. 4,025,990 (1977) to Lovette discloses a cryogenic process for recovering rubber in the form of crumb rubber, fabric and metal components from scrapped automobile tires.
U.S. Pat. No. 3,997,407 (1976) to Fuji et al. discloses dry distillation of scrap tires in a vertical dry distillation retort to recover carbon black and oil.
U.S. Pat. No. 4,250,158 (1981) to Solbakken et al. discloses pyrolizing used tires in an oxygen-limited hydrocarbon vapor at subatmospheric pressure to eventually recover carbon black, tar, oil and fuel gas.
None of these processes discloses the production of rubberized carbon black from worn automobile tires, nor is there disclosed novel compositions comprising rubberized carbon black and crumb rubber or polymeric materials or both crumb rubber and polymeric materials for the fabrication of useful articles, particularly those of unusual and valuable physical, mechanical and thermal properties.